This invention relates to a stripline cable in which a porous film of expanded polytetrafluoroethylene ("PTFE") resin having a plurality of continuous openings therethrough is disposed between electrical conductors.
Keen interest has been shown in use of polytetrafluoroethylene resin in high speed transmission lines such as stripline cables because of the advantageous features of this resin in that, when applied as a dielectric, it has a low dielectric constant and dielectric loss, and it is also stable chemically and physically. Attempts have been made to further reduce the dielectric constant of polytetrafluoroethylene resin by stretching it into a thin, porous film so that even higher performance transmission lines could be realized. However, these prior efforts to achieve the maximum performance for transmission lines have limits. My U.S. Pat. No. 4,382,236 and the references cited therein set forth the most relevant known prior art.